Behenic acid is a cholesterol-raising saturated fatty acid in humans

Background: Dietary behenic acid (22:0) is poorly absorbed. Because of its low bioavailability compared with other fatty acids and because of its very long chain length, the effect of dietary behenic acid (behenate) on serum lipid concentrations in humans is assumed to be neutral.

Objective: The objective was to establish the cholesterol-raising potential of behenic acid by comparing the effects on lipid and lipoprotein concentrations of a specially formulated fat enriched with behenic acid with those of palm oil (rich in palmitic acid; 16:0) and high-oleic acid sunflower oil (rich in cis oleic acid; 18:1).

Design: In a randomized, crossover, metabolic-ward study, 7 mildly hypercholesterolemic men were fed 3 natural-food diets supplemented with behenate oil, palm oil, or high-oleic acid sunflower oil. Mean serum lipid and lipoprotein concentrations and plasma triacylglycerol fatty acid composition were determined from fasting blood drawn during the final 4 d of each 3-wk diet period.

Results: Behenate oil produced mean concentrations of total Cholesterol (5.87+/-0.8 mmol/L) and LDL Cholesterol (4.40+/-0.8 mmol/L) not significantly different from those produced by palm oil (5.84+/-0.7 and 4.42+/-0.7 mmol/L, respectively) but significantly higher than those produced by high-oleic acid sunflower oil (5.12+/-0.5 and 3.70+/-0.6 mmol/L, respectively). There were no significant differences in triacylglycerol or HDL-cholesterol concentrations.

Conclusions: Despite its low bioavailability compared with oleic acid, behenic acid is a cholesterol-raising fatty acid in humans and is therefore not a suitable substitute for palmitic acid in manufactured triacylglycerols.